Direct inversion of differenced seismic reflection data for time‐lapse structural changes

Crosswell reflection method is a high-resolution seismic imaging method that uses recordings between boreholes. The need for downhole sources is a restrictive factor in its application, for example, to time-lapse surveys. An alternative is to use surface sources in combination with seismic interferometry. Seismic interferometry (SI) could retrieve the reflection response at one of the boreholes as if from a source inside the other borehole. We investigate the applicability of SI for the retrieval of the reflection response between two boreholes using numerically modeled field data. We compare two SI approaches — crosscorrelation (CC) and multidimensional deconvolution (MDD). SI by MDD is less sensitive to underillumination from the source distribution, but requires inversion of the recordings at one of the receiver arrays from all the available sources. We find that the inversion problem is ill-posed, and propose to stabilize it using singular-value decomposition. The results show that the reflections from deep boundaries are retrieved very well using both the CC and MDD methods. Furthermore, the MDD results exhibit more realistic amplitudes than those from the CC method for downgoing reflections from shallow boundaries. We find that the results retrieved from the application of both methods to field data agree well with crosswell seismic-reflection data using borehole sources and with the logged P-wave velocity.

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Time-lapse imaging using 3D ultra-high-frequency marine seismic reflection data

Geophysics ◽

10.1190/geo2019-0258.1 ◽

2020 ◽

Vol 85 (2) ◽

pp. P13-P25

Author(s):

Michael J. Faggetter ◽

Mark E. Vardy ◽

Justin K. Dix ◽

Jonathan M. Bull ◽

Timothy J. Henstock

Keyword(s):

High Frequency ◽

Seismic Reflection ◽

High Tide ◽

Time Lapse ◽

Data Set ◽

Seismic Reflection Data ◽

Near Surface ◽

Ultra High Frequency ◽

Reflection Data ◽

Marine Seismic

Time-lapse (4D) seismic imaging is now widely used as a tool to map and interpret changes in deep reservoirs as well as investigate dynamic, shallow hydrological processes in the near surface. However, there are very few examples of time-lapse analysis using ultra-high-frequency (UHF; kHz range) marine seismic reflection data. Exacting requirements for navigation can be prohibitive for acquiring coherent, true-3D volumes. Variable environmental noise can also lead to poor amplitude repeatability and make it difficult to identify differences that are related to real physical changes. Overcoming these challenges opens up a range of potential applications for monitoring the subsurface at decimetric resolution, including geohazards, geologic structures, as well as the bed-level and subsurface response to anthropogenic activities. Navigation postprocessing was incorporated to improve the acquisition and processing workflow for the 3D Chirp subbottom profiler and provide stable, centimeter-level absolute positioning, resulting in well-matched 3D data and mitigating 4D noise for data stacked into [Formula: see text] common-midpoint bins. Within an example 4D data set acquired on the south coast of the UK, interpretable differences are recorded within a shallow gas blanket. Reflections from the top and bottom of a gas pocket are imaged at low tide, whereas at high tide only the upper reflection is imaged. This case study demonstrates the viability of time-lapse UHF 3D seismic reflection for quantitative mapping of decimeter-scale changes within the shallow marine subsurface.

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A Scattering Description of Time-lapse Seismic Reflection Data with an Application to Difference Reflectivity Inversion

73rd EAGE Conference and Exhibition incorporating SPE EUROPEC 2011 ◽

10.3997/2214-4609.20149240 ◽

2011 ◽

Author(s):

K. A. Innanen ◽

M. Naghizadeh

Keyword(s):

Seismic Reflection ◽

Time Lapse ◽

Seismic Reflection Data ◽

Reflection Data ◽

Reflectivity Inversion

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A case history of experimental time-lapse 3C 2D seismic reflection data for reservoir monitoring at Cold Lake, Alberta, Canada

Interpretation ◽

10.1190/int-2013-0144.1 ◽

2014 ◽

Vol 2 (2) ◽

pp. SE47-SE54

Author(s):

J. Helen Isaac ◽

Don C. Lawton

Keyword(s):

Seismic Reflection ◽

Time Lapse ◽

Steam Injection ◽

Converted Wave ◽

Injection Wells ◽

Seismic Reflection Data ◽

Experimental Time ◽

Reflection Data ◽

History Of ◽

Cold Lake

We processed, interpreted, and analyzed experimental time-lapse converted-wave 2D-seismic reflection data that were acquired across a bitumen field undergoing cyclical steam injection and production at Cold Lake, Alberta, Canada. The purpose was to assess whether multicomponent-seismic data could be used to detect lateral and/or temporal changes caused by steam injection into the reservoir. We interpreted horizons on PP and PS sections that bracket the reservoir, and calculated [Formula: see text] over this interval. Away from the steam injection wells, [Formula: see text] values average [Formula: see text] during steaming and production and are close to the theoretically predicted value of 2.21 for a cold reservoir. Near the wells, [Formula: see text] is lower during steam injection than during production, averaging [Formula: see text], and the lowest values are observed close to the injection wells. We attributed the changes in [Formula: see text] to changes in the reservoir caused by the injection of steam.

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A Demonstration of Time-Lapse Imaging Using Ultra-High-Frequency Seismic Reflection Data

3rd Applied Shallow Marine Geophysics Conference ◽

10.3997/2214-4609.201802677 ◽

2018 ◽

Author(s):

M. Faggetter ◽

M. Vardy ◽

J. Dix

Keyword(s):

High Frequency ◽

Seismic Reflection ◽

Time Lapse ◽

Seismic Reflection Data ◽

Ultra High Frequency ◽

Reflection Data ◽

Time Lapse Imaging

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Reciprocity-based passive monitoring with individual sources

Geophysics ◽

10.1190/geo2018-0148.1 ◽

2019 ◽

Vol 84 (2) ◽

pp. KS29-KS38

Author(s):

Carlos Almagro Vidal ◽

Joost van der Neut ◽

Kees Wapenaar

Keyword(s):

Seismic Data ◽

Seismic Reflection ◽

Induced Seismicity ◽

Time Lapse ◽

Source Distribution ◽

Seismic Interferometry ◽

Image Domain ◽

Seismic Reflection Data ◽

Reflection Data ◽

Active Base

Time-lapse changes in the subsurface can be analyzed by comparing seismic reflection data from two different states, one serving as the base survey and the second as the monitor survey. Conventionally, reflection data are acquired by placing active seismic sources at the acquisition surface. Alternatively, these data can be acquired from passive sources in the subsurface, using seismic interferometry (SI). Unfortunately, the reflection responses as retrieved by SI inherit an imprint of the passive-source distribution; therefore, monitoring with SI requires high passive-source repeatability, which is very often not achievable in practice. We have developed an alternative by using active seismic data for the base survey and a single passive source (e.g., a seismic tremor produced by induced seismicity) for the monitor survey. By constraining the source-radiation pattern of the (active) base survey according to the characteristics of the (passive) monitor survey, we succeed in extracting the time-lapse response in the image domain. We tested our method with numerically modeled data.

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